FR2780346A1 - Refrigerant cooling circuit for vehicle climate control system - Google Patents

Abstract

The circuit comprises three branches (1,2,3) and a connector (15). A first entry (16) connects with a condenser (6), second entry (17) with a commutator vane (12) and an exit communicating with and evaporator (5). A non-return valve (8) is located is located at the first entry point at the three way connector.

Description

Refrigerant fluid circuit, especially for air conditioning

  tion of the passenger compartment of a motor vehicle The invention relates to a refrigerant circuit intended in particular for air conditioning the passenger compartment of a motor vehicle. It relates more particularly to a refrigerant circuit comprising a first branch containing an evaporator followed by a compressor, a second branch containing a condenser and a third branch not containing a condenser, the second and third branches being placed mutually in parallel so to train with the

  first branch respectively a cooling loop

  ment, also containing a pressure reducer, and a heating loop, as well as at least one switching valve for sending the fluid leaving the first branch, either in

  the second branch, or in the third branch.

  A refrigerant circuit of this type is known in

  particular according to publication FR-A-2 717 126.

  In this known circuit, means are further provided for sending into the passenger compartment of the air having undergone a

  heat exchange with the evaporator.

  Usually, such a circuit includes two valves

  three-way switching controlled by solenoid valves.

  These means allow the circuit to be placed in three configurations.

  different rations, in which it operates respectively

  as a classic air conditioning circuit, as a heating circuit and as a particular circuit in

  which the refrigerant accumulates in the evaporator.

  The Applicant recently proposed to simplify the realization

  tion of such a circuit by incorporating a component which can be connected to the three branches and internally housing the

  junction point of the three branches as well as the regulator.

  In a refrigerant circuit of the aforementioned type, when the switching valves are in a position such that the refrigerant, in gaseous form, is sent into the third branch, to thus reach the inlet of the evaporator, it is necessary to avoid a possible return of the fluid in the second branch which

contains the regulator.

  This is why we usually plan a

  non-return valve inserted on the second branch.

  In the solution recently proposed by the Applicant, the aforementioned component also incorporates this check valve, which

  which contributes to the simplification of the circuit.

  The main object of the invention is to simplify more

  tage the realization of a circuit of the aforementioned type by integrating a component grouping together several functions of the circuit. Another object of the invention is to integrate such a component to limit the number of circuit connections and therefore potential leaks, and also to reduce the overall cost of the circuit.

  To this end, the invention proposes a circuit of refrigerated fluid.

  rant of the type defined in the introduction, which comprises a connector provided with a first input suitable for being connected to the condenser, a second input suitable for being connected to the switching valve and a common output suitable for being connected to the evaporator, so that the first inlet, the second inlet and the common outlet end at a junction point common to the three branches, and in which the regulator and a non-return valve are housed in the fitting

  between the first entry and the junction point.

  Thus, the circuit of the invention incorporates a component produced in the form of a connector with two inputs and one output, which can also be called to simplify "T-connector", which connector incorporates the regulator and the valve. anti-return. Such a fitting can be easily integrated into the circuit, which limits the number of connections and potential leaks.

  and further reduces the overall cost of the circuit.

  According to another characteristic of the invention, the valve

  check valve is located between the first entry and the deten-

deur.

  Advantageously, the regulator comprises an expansion tube with calibrated orifice, surrounded by a sleeve introduced by force

  in a conduit that includes the fitting.

  In one embodiment of the invention, the connector comprises a main conduit provided with two opposite ends which constitute respectively the first inlet and the common outlet and a secondary conduit opening into the main conduit and provided with an end which constitutes the

second entry.

  The aforementioned connection can either be produced in the form of an individual component or else be integrated in a block.

of connection.

  Preferably, the connection block is provided with a direct through passage suitable for being inserted in the first

  branch between the evaporator and the compressor.

  This makes it possible to integrate, in a single component, both the aforementioned fitting and a passage or conduit suitable for being

  sandwiched between the evaporator and the compressor.

  In one embodiment, the connector comprises a main conduit provided with two opposite ends which constitute respectively the first inlet and the common outlet and a secondary conduit opening into the main conduit and

  provided with an end which constitutes the second entry.

  Advantageously, the direct passage and the main duct are substantially parallel and lead to two

  opposite sides of the connection block.

  It is advantageous for the direct passage and the main conduit to open on one of said opposite faces by respective orifices which allow a connection with the evaporator. According to another advantageous characteristic, the secondary conduit is substantially parallel to the main conduit, opens onto one of the opposite faces of the connection block and

  communicates with the main conduit through a transverse conduit

sal at the junction point.

  In another embodiment, in which the connection block is also provided with a direct through passage, the connector comprises a main conduit provided with a first end which constitutes the first inlet and with a second end which opens into a secondary duct, which

  has two opposite ends which respectively constitute

  the second inlet and the joint outlet of the fitting.

  Preferably, the direct passage and the secondary conduit are substantially parallel and open on two sides

opposite of the connection block.

  It is advantageous for the direct passage and the secondary conduit to open on one of the opposite faces of the connection block by respective orifices which allow a

connection with the evaporator.

  Preferably, the main conduit is substantially perpen- ted

  dicular to the secondary conduit and opens onto a face of the connection block which is perpendicular to said faces

opposite of the connection block.

  In the following description, made only as

  example, reference is made to the accompanying drawings, in which:

  - Figure 1 is a diagram of a refrigerated fluid circuit

  suitable for air conditioning and space heating

  tackle of a motor vehicle produced according to a first embodiment of the invention; - Figure 2 is a sectional view of the connector forming part of the circuit of Figure 1;

  - Figure 3 is a diagram of a refrigerated fluid circuit

  rant according to a second embodiment of the invention; - Figure 4 is a sectional view of the connection block forming part of the circuit of Figure 3; - Figure 5 is a sectional view of a connection block according to another alternative embodiment; and - Figure 6 is a sectional view along line VI-VI of the

figure 5.

  First of all, reference is made to FIG. 1 which represents a circuit in which a refrigerant fluid able to pass from the liquid state to the gaseous state by absorbing heat, circulates, and from the gaseous state to the state liquid by giving off heat, as is usually the case in

  air conditioning systems for motor vehicles.

  The circuit illustrated in FIG. 1 comprises three branches 1, 2 and 3 connecting together at two junction points A and B. Branch 1 contains a compressor 4 which circulates the fluid from point A to point B, and a evaporator 5 placed upstream of the compressor. The branch 2 contains, from point B to point A, a condenser 6, a bottle 7, a non-return valve 8 and a regulator 10. A second regulator 14 is placed in branch 3. A first three-way valve 11 is interposed in branch 1 so that two of its channels 11-1 and 11-2 communicate respectively with the outlet of the evaporator 5 and with the inlet of the compressor 4. A second three-way valve 12 is placed at the point junction B so that its three channels 12-1, 12-2 and 12-3 connect respectively to the downstream end of the first branch, that is to say to the outlet of the compressor 4, to the upstream end of branch 2, that is to say at the inlet of condenser 6, and at the upstream end of branch 3, that is to say at the inlet of regulator 14. Finally, a fourth branch 13, containing no component, connects the third track 11-3 of the solenoid valve 11 to an intermediate point C of the branch 2, lying between the

track 12-2 and the condenser 6.

  The structure of the circuit of FIG. 1 is known, so

  general, by the publication FR-A-2 710 726 already cited.

  In this circuit, the solenoid valves 11 and 12 are controlled

  in coordination to allow three configurations

  different conditions, already described in the above publication

  tee. In the configuration of Figure 1, each of the two valves communicates its numbered channels 1 and 2, as indicated by the two black triangles. The fluid then circulates in a closed loop formed by the branches 1 and 2, the branch 3 and the branch 13 being isolated by the valves 12 and 11 respectively. This loop functions like a conventional air conditioning circuit, the fluid passing from the liquid state to the gaseous state in the evaporator 5 by absorbing heat, and from the gaseous state to the liquid state in the condenser 6 in yielding heat. The heat absorbed in the evaporator 5 can be taken directly or

  indirectly, in an air flow F to be sent into the home

vehicle key.

  The circuit of FIG. 1 is suitable for adopting a second configuration (not shown) in which the valve 11 communicates its branches 1 and 2 and the valve 12 its branches 1 and 3, so that the fluid circulates in a closed loop constituted by branches 1 and 3. The fluid

  therefore passes through the compressor 4, the regulator 14 and the evaporator

  tor 5. No longer passing through the condenser, it remains perma-

  gas state. The evaporator 5 therefore no longer plays the

  role of evaporator, but continues to play the role of

  heat gor, making it possible to dissipate a large part of the heat produced by the compression of the fluid in the compressor 4, this heat being able to be used for heating the passenger compartment when the heat engine of the vehicle is cold. In particular, the fluid in circulation being at a temperature above ambient temperature, an air flow to be sent into the passenger compartment can be heated directly in contact with the evaporator. The presence of the two solenoid valves 11 and 12 instead of one makes it possible to isolate the condenser and to avoid parasitic fluid transfers by

  following changes in the volume of the fluid it contains.

  In addition, the circuit of Figure 1 can adopt a three-

  sith configuration (not shown) in which the valves ensure communication on the one hand between the channels

  11-3 and 11-2, on the other hand between channels 12-1 and 12-3.

  The inlet of the compressor is then connected, via the branch 13, to the normal inlet of the condenser, from which it can extract fluid in the gaseous state. This fluid then circulates in branch 3, but cannot return to the condenser from point A, in particular because of the presence of the

  check valve 8. The fluid therefore reaches the evaporator.

  tor 5, where it accumulates, the valve 11 not ensuring communication between the output thereof and the input of the compressor. The mass of fluid which will circulate in branches 1 and 3 after restoration of the configuration

previous is thus increased.

  According to the invention, the circuit of FIG. 1 comprises a connector 15 provided with a first input 16 suitable for being connected to the condenser 6, with a second input 17 suitable for being connected with the switching valve 12 and with a common outlet

  18 suitable for being connected to the inlet of the evaporator 5.

  The connector 15 comprises a main conduit 19 (Figures 1 and

  2), produced in the form of a straight tube of circular section

  laire, provided with two opposite ends which constitute

  respectively the first input 16 and the common output 18.

  The connector 15 further comprises a secondary conduit 20 (FIGS. 1 and 2) which opens out substantially perpendicularly into the main conduit (19). The first inlet 16, the second inlet 17 and the outlet 18 lead to the junction point A, which is thus contained in the connector 15. As can be seen more particularly in FIG. 2, the entrances 16 and 17 are produced under the form of tips suitable for being connected respectively to conduits (not shown) constituting the branches 2 and 3 of the circuit. The outlet 18 is also produced in the form of a nozzle capable of being fitted directly to the inlet of

the evaporator 5.

  The main duct 19 successively houses between the inlet 16 and the junction point A, the non-return valve 8 and the regulator 10 of the circuit. The non-return valve 8 is disposed directly in the inlet 16, while the pressure reducer 10 is disposed in a central region of the tube 19 between the inlet 16 and the junction point A. The secondary conduit 20 is substantially perpendicular to the

main duct 19.

  The regulator 10 comprises an expansion tube 21 (FIG. 2) with a calibrated orifice, surrounded by a sleeve 22 introduced by force

  inside the main duct 19.

  As a result, the connector 15 can be connected directly.

  on branches 2 and 3 of the circuit and at the entrance to the evapo-

  erator 5, which limits the number of connections

  of the circuit and therefore the potential leaks of the latter.

  The circuit of FIG. 1 can adopt any one of the three aforementioned configurations. In particular, in the aforementioned second configuration, in which the circuit operates in heating mode, the fluid in gaseous form

  from the switching valve 12 is sent direct-

  ment at the inlet of the evaporator 5, the non-return valve 8 opposing the return of the fluid in the second branch of the circuit. Reference is now made to FIG. 3 which shows another circuit operating in the same manner as that of FIG. 1. This circuit comprises a connection block 23 of generally parallelepiped shape, obtained by machining a

  block made for example of aluminum-based alloy.

  The connection block 23 is provided with a direct through passage 24 suitable for being inserted in the first branch 1 between the outlet of the evaporator 5 and the compressor 4. This block further comprises a connector 25 which plays the same function as the aforementioned connector 15 which is machined in the block. This connector is provided with a first input 26 suitable for being connected to the condenser 6, with a second input 27 suitable for being connected to the switching valve 12 and with a common output 28 suitable for being connected to the input of the evaporator 5. The connector 25 (FIGS. 3 and 4) comprises a main duct

  29 provided with two opposite ends which respectively constitute

  The first inlet 26 and the common outlet 28. The connector 25 further comprises a secondary duct 30 opening into the main duct 19, at the junction point A, and provided with an end which constitutes the

second entry 27.

  The direct passage 24 and the main duct 29 are sensi-

  clearly parallel and lead to two opposite faces 31

  and 32 of block 23. The direct passage 24 leads respectively to

  vement on the opposite faces 31 and 32 by orifices 33 and 34. The main tube 29 opens respectively on the opposite faces 31 and 32 by two orifices which constitute

  respectively the first entry 26 and the common exit 28.

  The orifice 34 and the orifice corresponding to the common outlet open onto the face 32 of the machined block to allow a

  direct connection with the evaporator 5.

  The secondary conduit 30 is substantially parallel to the main conduit 29 and opens onto the face 31 of the connection block. It communicates with the main duct 29 by a transverse duct 35 arranged obliquely. This transverse conduit comprises a first end which opens into the main conduit 29 at the junction point A and another end which opens onto a face 36 of the connection block, which is perpendicular to the faces 31 and 32. This

  other end of the conduit 35 is closed by a plug 37.

  The main duct 29 houses, between the inlet 26 and the junction point A, successively a non-return valve 8 and a

  regulator 10 similar to those described above.

  The connection block 23 of Figures 3 and 4 therefore offers the additional advantage of integrating a direct passage

  can be connected directly to the evaporator outlet

  5, which allows a direct connection with

  the inlet and outlet of said evaporator.

  In the embodiment of Figures 5 and 6, to which we now refer, the circuit also incorporates a connection block 43, which is provided with a direct through passage

  44 analogous to passage 24 of the foregoing embodiment

  tooth, and a fitting 45 similar to the fitting 25 described

previously.

  This connector 45 is provided with a first input 46 suitable for being connected to the condenser 6, with a second input 47 suitable for being connected to the switching valve 12 and with an output

  common 48 suitable for being connected to the entrance to the evaporator

author 5.

  The connector 45 comprises a main conduit 49 provided with a first end which constitutes the first inlet 46 and with a second end 51 which opens into a secondary conduit 50 similar to the secondary conduit 30 of the previous embodiment. This secondary conduit 50 has two opposite ends which respectively constitute the second inlet 47 and the common outlet 48 of the connector 45. The direct passage 44 and the secondary conduit 50 are substantially parallel and open on two opposite faces 52 and 53 of the block 43. passage 44 includes two orifices 54

  and 55 which lead respectively to the faces 52 and 53.

  Thus, the direct passage 44 and the conduit 54 lead to the face 53 respectively through the orifice 55 and through the orifice corresponding to the common outlet 48. It follows that these two orifices allow a direct connection with the evaporator 5. The main tube 29 successively houses, between the inlet 46 and the end 51 (which corresponds to the junction point A), a non-return valve 8 and a regulator 10 similar to those

  described in the previous embodiments.

  As can be seen in FIGS. 5 and 6, the main conduit 29 is substantially perpendicular to the secondary conduit 50 and opens, on the side of the inlet 46, on a face 56 of the connection block which is perpendicular to the

sides 52 and 53.

  The connection block 43 of Figures 5 and 6 operates from the

  same way as the connection block 23 of FIG. 4.

  Of course, the invention is not limited to the embodiments described above by way of example and

embraces other variations.

  Thus, for example, the circuit could further comprise a fluid accumulator disposed between the evaporator 5 and the

valve 11.

Claims (14)

Claims   1. Refrigerant circuit comprising a first   branch (1) containing an evaporator (5) followed by a compressor   seur (4), a second branch (2) containing a condenser   (6) and a third branch (3) containing no conden-   the second and third branches being placed mutually in parallel so as to form with the first branch respectively a cooling loop (1, 2), also containing a regulator (10), and a loop   heating (1, 3), as well as at least one switching valve   tion (12) for sending the fluid leaving the first branch (1), either in the second branch (2) or in the third branch (3), characterized in that it comprises: a connector (15; 25; 45) provided with a first inlet (16; 26; 46) suitable for being connected to the condenser (6), with a second inlet (17; 27; 47) suitable for being connected to the switching valve (12) and a common outlet (18; 28; 48) suitable for being connected to the evaporator (5), so that the first inlet, the second inlet and the common outlet end at a junction point (A) common to the three branches (1, 2, 3), and in that the regulator (10) and a non-return valve (8) are housed in the connection between the   first entry (16; 26; 46) and the junction point (A).   2. Circuit according to claim 1, characterized in that the non-return valve (8) is located between the first inlet (16; 26; 46) and the regulator (10).   3. Circuit according to one of claims 1 and 2, character-   rised in that the regulator (10) comprises an expansion tube (21) with calibrated orifice, surrounded by a sleeve (22) forcefully introduced into a conduit (19; 29; 49) which comprises the connection.   4. Circuit according to one of claims 1 to 3, character-   risé in that the connector (15) comprises a main duct (19) provided with two opposite ends which respectively constitute the first inlet (16) and the common outlet (18) and a secondary duct (20) opening into the main duct ( 19) and provided with an end which constitutes the second entry (27).   5. Circuit according to one of claims 1 to 4, character-   laughed in that the fitting (25; 45) is integrated in a block connection (23; 43).   6. Circuit according to claim 5, characterized in that the machined block (23; 43) is provided with a direct through passage (24; 44) suitable for being inserted in the first   branch (1) between the evaporator (5) and the compressor (4).   7. Circuit according to claim 6, characterized in that the connector (25) comprises a main conduit (29) provided with two opposite ends which respectively constitute the first inlet (26) and the common outlet (28) and a secondary conduit ( 30) opening into the main duct (29) and   provided with an end which constitutes the second entry (27).   8. Circuit according to claim 7, characterized in that the direct passage (24) and the main conduit (29) are substantially parallel and open on two opposite faces (31, 32) of the connection block (23).   9. Circuit according to claim 8, characterized in that   the direct passage (24) and the main conduit (29) open   chent on one (32) of said opposite faces by respective orifices (34, 28) which allow a connection with the evaporator (5).   10. Circuit according to one of claims 8 and 9, character-   laughed in that the secondary duct (30) is substantially parallel to the main duct (29), opens onto one (31) of the opposite faces of the connection block and communicates with the main duct (29) by a transverse duct (35 ), at junction point level (A).   11. Circuit according to claim 6, characterized in that the connector (45) comprises a main conduit (49) provided with a first end which constitutes the first inlet (46) and with a second end (51) which opens into a secondary duct (50), which has two opposite ends which respectively constitute the second inlet (47) and the   common outlet (48) of the fitting (45).   12. Circuit according to claim 11, characterized in that the direct passage (44) and the secondary conduit (50) are substantially parallel and lead to two opposite faces (52, 53) of the connection block (43).   13. The circuit as claimed in claim 12, characterized in that   the direct passage (44) and the secondary conduit (50) open   chent on one (53) of said opposite faces by respective orifices (54, 48) which allow a connection with the evaporator (5).   14. Circuit according to one of claims 12 and 13,   characterized in that the main duct (29) is sensitive-   perpendicular to the secondary duct (50) and opens   on a face (56) of the connection block (43) which is perpendicular   cular to said opposite faces (52, 53) of the machined block (43).